The FanSided guide to horse racing: What is a thoroughbred?

All the horses running in the Kentucky Derby will be thoroughbreds, but what exactly does that mean?

A thoroughbred race horse is one of the finest athletes on the planet. Their diet, exercise, and treatment of physical ailments is at least as closely monitored as anyone playing or training for a professional sport. And they also have the advantage of building on literally hundreds of years of selective breeding. Breeding looking to produce speed and (sometimes) stamina.

The thoroughbred breed began in England in the late 17th and early 18th century. That was when a trio of Barb or Arabian stallions came in and were bred to the local mares in order to add refinement and athleticism. Flat racing had existed beforehand, but it was nowhere near the wide-reaching sport it later became. The new horses so outclassed their poor English contemporaries, and became desirable enough that a whole new breed formed. Since then the breed has been maintained meticulously, and refined possibly to the point of excess.

The first thoroughbred was imported to the United States in 1730. And again, while there was some horse racing in the colonies at the time it was much less structured than it later became. Races were open to anyone who wanted to enter, regardless of breed, and were often held in whatever empty field a farmer had.

It took a while for the racing industry to emerge. People in those days were preoccupied with little things like the Revolutionary War. While informal racing existed pretty much the whole time, thoroughbred racing as a specific industry didn’t really take hold until after the Civil War. The American Stud Book (a precursor to the Jockey Club) was founded in 1868, and organized thoroughbred racing began shortly after. The first version of the Belmont Stakes, the oldest race in the Triple Crown, was held in 1867. The Preakness and Kentucky Derby showed up later, in 1873 and 1875 respectively.

As the racing industry grew, and became universally the thoroughbred’s industry, the breed became much more selective. This initially increased the quality of the horses, but has caused some problems in more recent years. The horses are bred for speed and athleticism. But choosing to focus solely on those traits has caused the demise of others. Some of these are soundness and mental stability. Like most animals that become highly bred, inbreeding increases over time, and causes problems, doubling down on any weaknesses the horses have, rather than eliminating them.

Next: 20 short stories about the 2018 Kentucky Derby horses

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